Actuating means for forging presses



A. K. NOWAK ACTUATING MEANS FOR FORGING PRESSES April 22, 1952 '3 Sheets-Sheet 1 Filed June 26, 1947 April 22, 1952 NOWAK ACTUATING MEANS FOR FORGING PRESSES 3 Sheets-Sheet 2 Filed June 26, 1947 did!!! April 22, 1952 Filed June 26, 1947 A. K. NOWAK ACTUATING MEANS FOR FORGING PRESSES 3 Sheeis-Sheet 5 Patented Apr. 22, 1952 UNITED STATES PATENT OFFICE ACTUATING MEANS FOR FORGING PRESSES Alois K. Nowak, Evanston, Ill.

Application June 26, 1947, Serial No. 757,193

among its important objects the provision of a forging press employing new and improved means for causing the movable anvil to reciprocate repeatedly at predetermined fixed time intervals.

Another important object of the invention is to provide a new and improved forging press wherein a novel combination of hydraulic and mechanical means are utilized to reciprocate repeatedly the movable anvil thereof at predetermined fixed intervals; other novel means being provided to vary the time interval between the repeat strokes of the anvil.

A further object is to provide an improved forging press wherein new and novel hydro-mechanical means are utilized to produce the down, or pressure, stroke of the movable anvil thereof, there being pneumatic means provided to move the anvil upwardly after completion of the pressure stroke.

A still further object is to provide a forging press wherein hydro-pneumatic safety means are provided to prevent the pressure exerted by the movable anvil from exceeding a predetermined amount.

Still another and more specific object of the invention is to provide a forging press wherein a source of hydraulic liquid supply is connected by a conduit to the movable anvil of the press, and a mechanical generator having a cylinder and a reciprocating piston 'is also connected into the conduit whereby each stroke of the piston in one direction will force the hydraulic liquid against the anvil to move it downward- 1y pneumatic means also being provided to elevate the anvil at the completion or the pressure stroke, whereupon the hydraulic liquid will be forced back into the cylinder during movement of the piston in the opposite direction.

A more specific object of the invention resides in the provision of a forging press, or any type or" machine where a member is caused to repeatedly perform an operation, with a hydraulic liquid to actuate the member, wherein liquid is caused to surge to and from the member by means of a reciprocating piston; electrically controlled by-pass means also being provided to control the surging of the liquid to and from, the member, or to and from the source of liquid supply, whereby the interval between the operating cycles of the membermay be varied while the reciprocation of the piston remains constant.

Numerous other objects and advantagesof the invention will become apparent upon reading 13 Claims. (Cl. 60-545) the following description taken in conjunction with the accompanying drawings in which:

Fig. 1 is an elevational view of a forging press embodying the invention and showing the relation between the press and its operating parts;

Fig. 2 is a somewhat enlarged elevational view, with parts broken away and in section, of the actuating means for the press andthe automatic controls therefor; and

Fig. 3 is a somewhat enlarged elevational view of the press with parts broken away and shown in section.

Heavy forging operations of the character for which the press of the present invention is particularly adapted for use have large reducing strokes for the ingot and require time intervals for manipulating the ingot between strokes. The time involved for the complete reducing of the ingot, in presses arranged only for single stroke operations, is dependent entirely upon the operator who may utilize more time than is necessary between strokes in manipulating the ingot. The present invention utilizes new and novel mechanism whereby the movable anvil of the press may be caused to cycle only once for single stroke operation, or the press may be caused to reciprocate repeatedly at predetermined intervals automatically for continuous repeat operations.

Briefly described, the invention contemplates the use of a hydraulic liquid which may be forced mechanically against the movable anvil through a conduit for causing the anvil to move downwardly for its pressure stroke. Release of the mechanical pressure against the hydraulic liquid then brings into use a pneumatic pull-back arrangement for elevating the anvil back to its original position. The mechanical means used involves a cylinder and reciprocating piston arrangement so that on the release stroke of the piston, the hydraulic fluid will return to the cylinder thereof. The movable anvil of the press will be actuated upon each stroke of the piston for continuous repeat operations at maximum speed. Automatically controlled bypass means are provided, however, for directing the hydraulic fluid to its source of supply instead of to the movable anvil upon certain predetermined strokes of the piston. The anvil will not be operated during these strokes, and thus the bypass means may be utilized for varying the time intervals between pressure strokes without interfering with the continuous reciprocation of the piston.

The invention also contemplates the use of 3 novel daylight adjusting means for adjusting the daylight opening between the two anvils of the press regardless of the position of the movable anvil, and whether the latter anvil is in motion or at rest. The press is designed to operate at a certain predetermined pressure, and therefore, a novel form of safety means is provided to prevent the pressure exerted by the movable anvil from exceeding the predetermined pressure.

One form of mechanism whereby the foregoing objects of the invention may be accomplished is illustrated in the drawings to which particular reference will now be made. in general, may be of more 01' less conventional design, having a sturdily supported base I on which a stationary anvil 2 is adapted to be secured. An ingot 3 upon which the forging opera' tions are to be performed is placed upon the anvil 2 by the operator, the forging press illustrated being of the four column type wherein columns 4 extend upwardly from the base I and are adapt ed to have a reciprocating carriage 5 slidably mounted thereon. A movable anvil 6 is suitably secured to the underside of the carriage 5, and this anvil is adapted to be moved downwardly against the ingot 3 for thepressure stroke, and upwardly away from the ingot upon release of the anvil.

The movable anvil fi'isadapted to be operated hydraulically, the carriage 5 therefor being pro with-an inwardly extending annular rib 9 to be. v received within a corresponding annular groove at the lower part of the plunger 1. The plunger I is mounted for vertical reciprocation within a cylinder it which has a hydraulic liquid inlet I I at the upper part thereof connected to duit'I2.

The conduit I2 extends over to the actuating mechanism, Figs. 1 and 2, and there may enter a suitable housing I3. A hydro-pneumatic surge tank I4 contains a quantity of hydraulic liquid 1 5 which is normally under a predetermined pressure exerted thereon by means of a pump I5 and by the conduit I7. An outlet I8 from the tank I4 permits the hydraulic liquid to enter a pneumatically controlled valve housing I9 which then carries the liquid through a conduit to the housing I3 and through the conduit l2.

The valve housing is is provided with an inlet EI and an outlet 22 between which are located two valves, a check valve 23 and a pneumatically;

operated valve 24. The purpose of the check valve will appear hereinafter, but for the present reference will be specifically made to the pneumatically operated valve 24 which is mounted for vertical reciprocation within the valve housing to open and close the passage 25 between the inlet andoutlet 2I and 22 respectively. A' valve stem 26'extends downwardly from the valve and is pro.- vided at its lower end with a piston 21 which is mounted for reciprocation within a cylinder house ing 28. This cylinder housing 28 is provided with passages 29 and 3B, the passage 29 being connected to a conduit 3i and the passage 39 being connected to a conduit 32. Both of these conduits may befconnected to any suitable source of air under pressure as designated by the numeral 33. Air under pressure which passes through the conduit'SI and through the passage 29, will. cause the piston 2'5 and the 'rod 26 connected to the 'valve 24, to be moved upwardly to open the The forging press, c

a con L passage 25 and permit the hydraulic fluid under pressure to enter the conduit 26. Air under pressure which passes through the conduit 32 and into the passage 30, will cause the piston 21 and valve 24 to be moved and held in a. downward or closed position, and thus prevent the passage of any fluid to or from the conduit 28.

' The power generator, which is utilized herein for actuating the movable anvil through the medium of the hydraulic liquid, comprises a suitable cylinder 34, having an opening 35 in the top thereof, connected with the housing E3. The cylinder 34 may be mounted in any desired manner such as by means of a support 36 connected to upwardly extending standards 37 on a housing 38. A reciprocating piston 39 is adapted to reciprocate'within the cylinder 34, and this piston 39 has secured at its lower end a connecting rod 49. The connecting rod 40 may be secured, such as by means of the wrist pin 4|, to an annular member. 42 surrounding an eccentric 43 on a drive shaft 44. The connecting rod 40 extends downwardly into the housing 33 and is guided by a bearing member 45. Rotation of the drive shaft 44, which carries with it the eccentric 43, will cause repeated reciprocation of the'piston 39 within the cylinder 34.

When the valve 24 is opened, and the hydraulic fluid under pressure from the surge tank I4 is permitted to pass into the conduit 20, the cylinder 34 as well as the conduit I2 to the plunger I will be completely filled with the liquid. If the valve 24 is then closed, the liquid will be prevented from reentering the surge tank l4 so that each upward stroke of the piston 39 will cause a displacement of the liquid in the conduit I2 and will force the movable anvil 6 downwardly by means of the pressure of the liquid against the plunger 1.

A novel form of pneumatic pull-back means is provided for elevating the movable anvil during the downward movement of the piston 39 to displace the hydraulic liquid back into the cylinder 34. The pull-back means are illustrated more clearly in Fig. 3, and consist of two cylinders, 45 and 41, suitably mounted on opposite sides of the columns and above the carriage 5. Each cylinder is provided with a piston 48 having a piston rod 49 connected thereto, the piston rod extends downwardly below the cylinder. The lower end of each piston rod 49 is suitably connected, as at 50, to the carriage 5 upon which the movable anvil 6 is mounted. A passageway 5i connects with the cylinder 46, also with another passage (not shown) from the cylinder 41, and this passageway leads to a pneumatic tank 52, which is normally under a predetermined constant air pressure at all times. The passage 5| remains open so that the air pressure is always present in the cylinders 46 and 41 normally maintaining or urging the pistons48 and the carriage 59 to their upward position. Thus, the pressure exerted against the plunger I by means of the piston 39. against'the hydraulic fluid will be suificient to overcome the air pressure in the cylinders 46 and a 41 to cause the downward pressure stroke of the Reciprocation of the piston 39, through the eccentric 43, will cause a continuous and repeated operation of the movable anvil of the press in predetermined fixed cycles. Each cycle will be equal to the reciprocation of the piston 39 as long as the valve 24 remains closed. This cycle will also be maintained even though the valve 24 may be opened during the downward stroke of the piston 39, because of the pressure in the tank l4 and the vacuum created by the downward movement of the piston within the cylinder 34. This fact is mentioned because the particular means disclosed herein for actuating the movable anvil upon each upward .stroke of the piston is such as to open the valve 24 upon each downward stroke thereof, as will become apparent hereinafter.

In accordance with the present invention it is alsopossible to have the movable anvil remain at rest at alltimes during reciprocation of the piston 39' if the valve 24 remains open. Thus, the pressure exerted by the pull-back arrangement may be greater than the: pressure in the surge tank ['4 and, when the conduits I2 and 2B and the cylinder 34 are completely filled with the hydraulic liquid 15, and the piston 39 moves upwardly when the valve 24 is open, the displacement of: the liquid will take place through the valve and back into the tank 14. Means; (not shown) may be provided for holding the valve 24 open when it is desired to have the press remain at rest so that continued reciprocation of the piston 39 will merely cause the hydraulic fluid to surgeback and forth between the cylinder 34 and the surge tank l4.

Any ordinary and well known means can be utilized for actuating the press for a single stroke only. This may be done either by causing a single reciprocating stroke of the piston 39 or by utilizing suitable means for closing the valve 24 for one cycle and then permitting it to remain open thereafter. Additional electrical means similar to that hereinafter described with respect to the varying of the cycles of the press may be utilized either for the idling strokes or for the single stroke of the movable anvil.

The pneumatic operation of the valve 24 is preferably controlled by energizing and de-energizing the solenoid 53 which may have connected thereto a lever arm 54. The lever 54 is adapted to be moved when the solenoid is operated to operate any suitable type of valve to direct air pressure either through the conduit 3| or 32.

A control panel may be located in a desirable position near the operator of the machine, which control panel may have a plurality of control switches diagrammatically illustrated in Figs. 1 and 3' and identified by the numerals 55, 55 and 51. The switch 55 may be utilized for causing a single stroke of the press, while the switch 56 may be utilized to cause continuous or repeated operation of the press at maximum speeds. The shaft 44 (see Fig. 2) has mounted thereon a cam 58 having a high side 59 and a low side 60-. The high and.- low sides of the cam 58 each cover about one-half of the periphery of the cam, the high side being adapted to contact the movable blade SI of the cam operated switch 62. The switch 62 may be of any suitable and well known type which is caused to complete a circuit through the solenoid 53 when contacted by the high side of the cam 58, and to break the circuit through the solenoid when the low side of the cam 58 is adjacent thereto; Assuming that the valve 24- is normally open when the solenoid 53 is de-energized, the closing of any circuit to the solenoid will then energize it and cause air to pass through the conduit 32 to close the valve 24. The

electrical circuit is simply one which is connect-- 6, ed to the solenoid and requires the closing of two switches. for energizing purposes. Thus, during the idling operation, the valve 24 will be open normally, as will the switches 55, 56 and El, so

that the closing of the switch 62 will have no efiect on the solenoid. If, however, the switch 56 is manually closed, then closing of the switch 62 will complete the circuit to energize the solenoid 53 and cause the valve 24 to close. When it is desired to cause repeated operation of the press at maximum speeds, the switch will be closed manually, whereupon continued rotation of the shaft. will move the switch arm 5| to close the switch 62 by operation of the high side of the cam 58. Thus, from, viewing Fig. 2, it will. be evident that the eccentric 43 is about to move the piston 39 upwardly by rotation thereof in a counter-clockwise direction. At this point the high side of the cam 58 will have closed the switch 62 and, since the switch 55 is also closed, the solenoid 53 will be energized to operate a valve to pneumatically close the valve 24. The upward movement of the piston 39 then will impart a pressure stroke to the movable anvil 6. A one-ha1f revolution of the shaft 44 will complete the pressure stroke and, during the downward movement of the piston 39, the low side of the cam 58 will permit the switch 62 to open and break the circuit to. the solenoid 53, thus deenergizing the solenoid and permitting the valve 24 to open. The displacement of the hydraulic liquid, however, will be to the cylinder 34 so that when the switch 52 is again closed to energize the solenoid 53 at the beginning of the next upward stroke of the piston 39, the valve 24 will again be closed and another cycle of the movable anvil will take place.

It will be cl ar that any control over the actu ation of the valve 34 in a predetermined manner may be utilized to control the interval between the pressure strokes of the anvil. For example, a similar form of camming device is illustrated herein whereby the cycle of operation may be divided in half. That is to say, the interval between pressure strokes of the press will be twice as long. In order to do this a second cam 63 mounted on a shaft 64 is caused to rotate 'by means of a pulley 65 and a belt 65 passing around another pulley on the shaft 44. This cam 63 is also provided with a high side 51 and a low side 68, each of which consumes one-half of the periphery of the cam. The ratio of this cam '63 to the cam 55 is such that it will rotate only once during two complete revolutions of the shaft 44. A control switch 63 has an arm it! which is adapted to be contacted by the high side 67 of the cam 63 to complete an electrical circuit to the solenoid 53 when the manually operated switch 5'! is closed. In this latter event the other two switches 55 and 56 will be open so that the operation of the valve 24 will be completely controlled by the rotation of the cam 63. It has been explained hereinabove that the hydraulic fluid will surge back and forth between the cylinder 34 and the tank i l during reciprocation of the piston 39 when the valve 24 is open. The position of the cam 63 in Fig. 2 is such that the high. side of the cam has justclosed the switch 69 to energizethe circuit to the solenoid 53 for the purpose of closing the valve 24. During a one-half revolution of the cam 53 the piston 35 will havemade a complete up-and-down stroke for actuating the movable anvil throu h one complete cycle. At this point the low side 58 of the cam 63 will arrive at the switch arm Hi to permit the switch to open and de-energize the solenoid 53 to open the valve 24. During the next one-half revolution of the cam '63 the piston 39 will reciprocate while the valve 24 is open thus displacing the hydraulic fluid to the tank I4 and then back to the cylinder 34. During thislatter stroke, the press will not be operated. The closing ofthe switch 51, then, will cause'the piston 39 to actuate the movable anvil through one cycle, whereupon the piston 39 will have an idling stroke or cycle during which time the press will not operate. The interval between the pressure strokes of the movable anvil will therefore have been doubled. Other similar means may be provided-forlengthening the interval between pressure strokes to any desired length of time, in multiples of time, which is required for a complete reciprocation of the piston 39.

As a specific example, if the piston 39 reciprocates at the rate of forty times per minute, the closing of switch 59 will produce a pressure stroke of the anvil every one and one-half seconds. If, however, the switch fi'l is closed, instead of the switch 53, the anvil will make a complete stroke in one and one-half seconds, then remain idle for one and one-half seconds before making the next stroke. These time intervals may be increased in multiples of one and one-half seconds to any desired limit by the use of additional means. 7

While any desired pressure on the movable anvil 6 may be obtained against the ingot 3, in actual practice the machine illustrated herein has been designed for a pressure of 2,000 tons. In order to render the operation of the machine entirely foolproof, and at the same time produce maximum results from the capacity available in the equipment, a hydro-pneumatic intensifier generally indicated by the numeral H is provided to limit positively the maximum pressure of thepress to 2,000 tons. This intensifier consists of a hydraulic cylinder 12 superimposed upon a large diameter pneumatic cylinder 13 connected by means of a conduit 14 to the air tank 15 which maintains a constant pressure within.

the cylinder 73 of approximately 200 pounds per square inch in the illustrated example. This pressure is maintained by means of the air compressor l6 and is exerted on the underside of the piston ll thus maintaining it normally in the upper position shown in Fig. 3.

The hydraulic cylinder 12 is provided with a piston '18 adapted to reciprocate therein and which is connected at its lower end with the piston ll in the pneumatic cylinder. The specific pressures mentioned herein are illustrative only and will apply only to the 2,000 ton press and it will be obvious that changes in the proportions and sizes of the press and its component parts will necessitate a corresponding change in the specific pressures used. In the present instance the total pressure against the piston H can only :be balanced by a pressure of 6,000 pounds per square inch on the plunger 18. The hydraulic cylinder 12 is connected with the plunger 1 of the movable anvil of' the press by means of the conduit 19. .It will therefore be evident that whenever a pressure of-6,000' pounds per square inch is generated in the press, the piston ll of the intensifier will yield and absorb any displacement from the piston 39 of the power generator at this pressure. a

The power generator heretofore described and illustrated in Fig. 2 may be operated by two motors in the neighborhood of 500. H. P. each,

having a fly wheel 99 mounted for rotation on a shaft 8| and which drives a pinion 82 on the main drive shaft 83. The pinion is in mesh with a large gear 89 on the shaft 14 to thereby eifect reciprocation of the piston 39. 7

Any displacement of the hydraulic fluid which may be passed into the cylinder 12 of the intensifier will be returned to the power generator cylinder 34 during the first part of the return stroke of the piston 39, at which time the intensifier will act as the drive of the generator and return to the fly wheel of its drive the energy it absorbed during the up stroke of the piston 39. A substantial dash pot may be provided to cushion the return stroke of the intensifier piston 11.

The intensifier limits the maximum pressure to 6,000 pounds per square inch or the capacity of the press to 2,000 tons. Any over-travel of the intensifier is prevented by a' cam operated limit switch 85 having a switch arm 86 to be contacted by the cam surface 01 of the rod 88 which will electrically open the by-pass valve 24 thereby automatically exhausting all pressure. It is within the contemplation of the present invention to insert in the electrical circuit at a suitable place an electric light bulb (not shown) which will become lighted when the intensifier reacts to 6,000 pounds pressure, or when pressure on the press reaches 2,000 tons. A skilled operator will then know that the press is being operated to the full capacity thereof when the light bulb flashes at every stroke.

The invention also includes the feature of providing means by which the daylight opening of the press may be adjusted. The distance between the anvil blocks 2 and 6 may be instantaneously and repeatedly changed by the provision of 'an oil hydraulic pumping unit consisting of a radial piston type pump and motor 89 connected to an oil reservoir 99. Two hydraulic cylinders 91 and 92 are located at the top of the press and are provided with plungers 93 which bear against the top side of the movable carriage 5. A suitable hydraulic valve 94, of any well known type of construction, has a conduit acting as a return to the reservoir 90, a conduit 96. connected to the pump and another conduit 91 which extends from the valve 94 to the cylinders 9| and 92. When the hydraulic liquid is pumped into the cylinders 9! and 92, the anvil will move downwardly and when these cylinders are exhausted, the anvil will move upwardly. Since this latter adjustment is entirely independent from any operating mechanism of the press, the adjustment may be made whether the press is standing still and the generator is idling, or the press is stroking and the generator is discharging into the press. In the former case where the press is standing still, the movable anvil canfirst be adjusted to maximum or minimum daylight or anywhere in between, and stroking of the press can then be started and will continue with this adjusted daylight. If the adjustment is made while daylight adjustment, the pressure against the anvil will be released, and'the presure in'the tank 14 will then open the valve 23 to permit the liquid to flow into the conduit l2 and fill the created void. When the pressure has reached equilibrium, the valve 23 will then close. When the anvil is raised for the daylight ad justment in the other direction, pressure in the conduits will return the excessive hydraulic liquid to the tank 14 through the open valve 24, which opens intermittently, as above explained.

A number of advantages will appear in the use of the press herein described and illustrated as a preferred embodiment of the present invention. For example, all of the operations are automatic and nothing is left to the judgment of the operator. Full pressure is assured at every stroke because the valve 24 will not open until the end of a stroke, norwill it close until the cylinder 34 is completely filled with the hydrauiic fluid. This advantage is obtained by means of the earns 58 and 63 which will not actuate the valve 24 until the proper time regardless of when the manually operated switches are actuated. If the operator desires to change the stroke of the press and 'aotuates one of the manual switches 56 or 51 in the middle of a stroke, the press will complete its current stroke before the valve will open or close to produce a change.

In order to illustrate more clearlythe opera tion of the machine and the advantages derived therefrom, a specific series of operations may be briefly described in the typical reduction of a Copperweld 7,500 pound ingot where the dimensions thereof are approximately 26 inches in diameter at the large end, 18 inches in diameter at the small end and '75 inches long.

Seconds 1st pass 2 strokes from 26" to 22" 'high 6 2nd pass 4 strokes from 22" to 18", length 84" 12 Turn 1% 3rd pass 3 strokes from 28" to 24" high 12 4th pass 3 strokes from 24" to 20", length 90" 12 Turn 1 /2 5th pass 5 strokes from 21 to 17" high,

length 96" 15 Turn 1 6th pass 5 strokes from 23" to 19" high,

length 102" 15 Turn L /2 7th pass 6 strokes from 19" to '17 high,

length 105" planish 9 Turn 1% 8th pass 6 strokes from 19" to 17" high,

length 108" planish 9 Total forging time 97 This will result in a production of 37 ingots per hour, not counting the changing of the ingots in the manipulator. On larger ingots in the neighborhood of 10,090 pounds, a similar estimate results in 12 passes with 30 long strokes and 15 planishing strokes requiring a total of 136 seconds, or a production of 26 ingots per hour.

To a great extent the automatic operation of the press sets the production rate. The automatic repeat cycles are fixed and the operators attention is confined only to the feeding of the ingot. The uniformity of each pressin stroke, which usually includes 4 inch pressure strokes at 20 strokes per minute or 2 inch pressure strokes at 40 strokes per minute, with its automatic reversal at the exact predetermined distancebw tween the anvil blocks eliminates the judgment of the operator, saves time and results in smooth surfaces on the forged billet free from steps and ridges. Furthermore, the power used is the power required to forge the ingot. No excess power is wasted such as excess pressure in hydraulic accumulators or steam pressure in intensifier-s.

It will be evident that various changes may be made in the form, arrangement and construction of parts from that disclosed herein without in any way departing from the spirit of the inventionor sacrificing any of the attendant advantages th reof, provided, however, that such changes fall within the scope of the claims appended hereto.

iiavin thus described my invention what I ciaim as new and desire to secure by Letters Patent of the United States is: i

1. A forging press of the class described, comprising stationary and movable anvils, a storage tank for a hydraulic liquid supply, generator means connected with said tank for generating hydraulic power, means connecting said generator means with the movable anvil and adapted to utilize the hydraulic liquid to move said anvil for the pressure stroke thereof, valve means for bypassing the liquid and directing it to said tank instead of to the movable anvil upon predetermined reciprocating cycles of said generator, and means to actuate said valve means at predetermined intervals, whereby continuous operation of said generator will produce a pressure stroke of the movable anvil repeatedly at predetermined fixed intervals.

2. A foregoing press of the class described, comprising stationary and movable anvils, hydraulic means for imparting a pressure stroke to said movable anvil at predetermined intervals and under a predetermined pressure, pneumatic means for continuously urgin said movable anvil in a direction opposite to the pressure stroke thereof to thereby move the anvil upon release of the hydraulic pressure thereagainst, and pneumatic safety means for preventing the pressure of the anvil from exceeding said predetermined pressure.

3. A forging press of the class described comprising stationary and movable anvils, a hydraulic system, a reciprocating plunger in said systemfor automatically imparting a pressure stroke to said movable anvil repeatedly at prodetermined intervals, and electrically controlled pneumatically operated valve means operable to vary the duration of the time intervals between which the pressure strokes of said movable anvil repeatedly occur.

4. A forging press of the class described comprising stationary and movable anvils, a hydraulic system, a reciprocating plunger in said system for automatically imparting a pressure stroke to said movable anvil repeatedly at predetermined intervals, and electrically controlled means inciuding a solenoid actuated and pneumatically operated valve operable to vary the I duration of the time intervais between which nected with said source of hydraulic liq uid suply, a hydraulic passage connecting said generator with said member, means to reciprocate said piston whereby said member is repeatedly actuated by the hydraulic pressure thereagainst created by repeated movement of said piston, and electrically controlled pneumatically operated valve means to vary the fixed cycle of operation of said member while maintaining the reciprocation of said piston constant.

6. In a machine wherein a movable member is adapted to repeatedly perform an operation, a source of hydraulic liquid supply, a mechanical generator for generating hydraulic power having a cylinder and piston therein connected with said source of hydraulic "liquid supply, a hydraulic passage connecting said generator with said member, means to reciprocate said piston whereby said member is repeatedly actuated by the hydraulic pressure thereagainst created by movement of said piston, valve means operable when open to divert the hydraulic liquid to said source of supply instead of to said member upon reciprocation of'said piston, and electrically controlled pneumatic means to open said valve at :predetermined intervals to vary the fixed cycle of operation of said member while maintaining the reciprocation of said piston constant.

'7. In a machine wherein a movable member is adapted to repeatedly perform an operation, a source of hydraulic liquid supply, a mechanical generator for generating hydraulic power having a cylinder and piston therein connected with said source of hydraulic liquid supply, a hydraulic passage connecting said generator with said member, means to reciprocate said piston whereby said member is repeatedly actuated by the hy-.. draulic pressure thereagainst created by movement of said piston, pneumatically operated valve means operable when open to divert the hydraulic liquid to said source of supply instead Of to said member upon reciprocation of said piston, and an electrically operated solenoid adapted to' open said valve at predetermined intervals to vary the fixed cycle of operation of said member while maintaining the reciprocation of said piston constant.

8. A forging press of the class described comprising stationary and movable anvils, a source of hydraulic liquid supply under pressure, mechanical means for applying said hydraulic liquid under pressure to the movable anvil for imparting a pressure stroke thereto, independent fluid means for regulating the daylight opening between the anvils regardless of the position of the movable anvil, and valve means operable by the pressure in said source for automatically con- 'of said fluid therethrough, pneumatic means for actuating said valve, a plurality of electrical control circuits each adapted to actuate said pneumatic means, a conduit connecting said valve with said anvil, a plunger mounted for reciprocation within a cylinder and connected with said conduit between said valve and anvil, whereby movement of said plungerv will cause the fluid to actuate said anvil when said valve'is closed, but

, force the fluidinto said tank whensaid valve;

12 is open, drive mean for continuously reciprocating said plunger, a normally open manually operable master switch in each of said circuits, a normally open mechanically operable switch in each of said circuits, actuating means for each of said under'pressure, valve means connected withsaid tank and operable, when open, to permit flow of said fluid therethrough, valve operating mean for actuating said valve, a mechanical actuator for generating hydraulic power, conduit means connecting said actuator with saidlvalve and with said anvil, whereby said actuator will force said fluid to said anvil when said valve is closed and to said tank when said. valve is open, drive means for said actuator, a plurality of electrical control circuits each adapted to control the operation of said valve operating mean for closing said valve for a difierent predetermined time interval, and switch means operated by said drive means to close a selected circuit.

11. In a hydraulic forging press, a hydraulically operated movable anvil, a storage tank for hydraulic fluid, means to maintain said fluid under pressure, valve means connected with said tank and operable, when open, to permit flow of said fluid therethrough, valve operating means for actuating said valve, a reciprocating plunger, conduit means connecting said plunger with said valve and with said anvil, whereby said plunger will force said fluid to said anvil when said valve is closed and to said tank when said valve is open, drive means for said plunger, a plurality of electrical control circuits each adapted to control the operation of said valve operating means for closing said valve for a different predetermined time interval, and switch means operated by said drive means to close a selected circuit.

12. In a hydraulic forging press, a hydraulically operated movable anvil, a storage tank for hydraulic fluid, means to maintain said fluid under pressure, valve means connected with said tank and operable, when open, ,to permit flow of said fluid therethrough, pneumatic means for actuating said valve, a mechanical actuator for generating hydraulic power, conduit mean connecting said actuator with said valve and with said anvil, whereby said actuator will force said fluid to said anvil when said valve is closed and to said tank when said valve is open, drive means for said actuator, a plurality of electrical control circuits each adapted to control the operation of said pneumatic means for closing said valve for a difierent predetermined time interval, and switch means operatedby said drive means to close a selected circuit.

13. In a hydraulic forging press, a hydraulically operated movable anvil, a storage tank for hydraulic fluid, means to maintain said fluid under pressure, valve means connected with said tank andoperable, when open, to permit flow of said fluid therethrough, pneumatic means for 13 conduit means connecting said plunger with said valve and with said anvil, whereby said plunger will force aid fluid to said anvil when said valve is closed and to said tank when said valve is open, drive means for said plunger, a plurality of electrical control circuits each adapted to control the operation of said pneumatic means for closing said valve for a different predetermined time interval. and switch means operated by said drive means to close a selected circuit. ,1

ALOISK; NOWAK.

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